MEXICO CITY — Mexican officials said Thursday that at least 18 Cubans have reached Texas more than a week after masked gunmen hijacked an immigration bus in southern Mexico and seized them.

The hijacking shows the increasingly violent methods of groups that smuggle Cubans through Mexico to the United States, and has prompted Mexico's government to probe corruption among its own immigration workers.

Mexico's Attorney General's Office said in a statement that the U.S. Border Patrol detained the immigrants in Hidalgo County in Texas and that they were in good health.

Officials with the U.S. Border Patrol in Texas said they could not immediately confirm the Cubans had been detained.

About six masked gunmen with assault rifles hijacked the bus along a remote jungle highway June 11. They forced seven unarmed immigration agents and two drivers to get off before they fled with 33 Cubans and four Central Americans who were being taken to a detention center for undocumented migrants.

Some Cubans missing
The bus was later found abandoned and the whereabouts of the remaining migrants was not immediately known.

The Attorney General's Office said that the Cubans used fake Mexican identifications to reach the U.S. border.

Nine Mexican immigration officials and the two bus drivers have been detained for investigation of possible involvement in the hijacking, the Attorney General's Office said.

Mexico's navy found the 33 Cubans two weeks ago on a yacht off of Cancun. The migrants told authorities they had left Cuba on a makeshift boat and while at sea were spotted by two men in a yacht who offered to take them to the U.S.

The Attorney General's Office said police detained Nairobi Claro Ortega and Noriel Veloz on allegations the men brought the immigrants from Cuba to Mexico.

The men, both of Cuban origin and with residences in Miami, turned down an offer of bail, saying they feared for their lives, the Attorney General's Office said.

Growing business, and dangerIn recent years, Mexican officials say they have detected Cuban Americans involved in human trafficking rings in the Yucatan Peninsula, which lies just 120 miles southwest of Cuba.

Several of the alleged smugglers have turned up dead in the Yucatan.

For decades, Cubans quietly passed through Mexico to avoid being caught at sea by U.S. Coast Guard patrols between the communist-run island and Florida. Under U.S. policy, Cubans intercepted at sea are generally sent back while those who reach U.S. soil are allowed to stay.

Smugglers have turned human cargo into big business in recent years, sometimes getting $300,000 or more to take a boatload of Cubans directly to Florida.

So far this year, Mexican immigration agents have detained more than 1,000 Cuban immigrants. Last year, officials detained 1,359 Cubans.

Most Cubans who arrive in Mexico are released after being held for months at an immigration center.

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